Lysis of Microcystis aeruginosa with extracts from Chinese medicinal herbs.

Boiling water extracts of 66 selected Chinese medicinal herbs were screened for their anticyanobaterial activity against Microcystis aeruginosa by the soft-agar overlayer (SAO) method. Results indicated that extracts from 16 materials could inhibit the growth of this bacterial species. Among these anticyanobacterial samples, eight extracts showed low minimum inhibitory concentrations (MIC), including four extracts with MICs between 1 and 6 mg/mL, and four extracts with MICs < 1 mg/mL which could be considered useful to prevent the outbreak of cyanobacteria before the appearance of cyanobacterial blooms.

Isolation of a Methylobacillus sp. that degrades microcystin toxins associated with cyanobacteria.

Sludge from cyanobacteria-salvaged yard in Meiliang Bay, Lake Taihu in Wuxi, China was cultured and acclimated by inoculating microcystins (MCs) extract. Strain J10 was isolated by degrading the MC-RR and MC-LR and was identified as Methylobacillus sp. Further research showed that both MC-LR and MC-RR could be completely degraded at 17h after inoculation of J10, and the degradation probably was mediated by oxygen.